NEW!  Super bright Helium spectrum discharge tube 100mm - NEW This new discharge tube is a redevelopment of our luminescent ampoules and offers the benefits of a metal-free ampoule with the luminosity of a commercial spectrum tube. In this tube, the excited gas  has to pass through many small capilaries and is forced to particularly strong shine. Good contact between the external electrodes around the ampoule is required. Made of high quality shock- and heat proof boro silicate glass.    You can easily let it glow with a tesla generator. Lengh: 10cm, dia. ~12mm Operating voltage 5000V @ 20mA - available here in our shop This is a very special piece for a complete elements collection !!!